Heat generating devices, such as power semiconductor devices, may be coupled to a heat spreader to remove heat and lower the maximum operating temperature of the heat generating device. In some applications, cooling fluid may be used to receive heat generated by the heat generating device by convective thermal transfer, and remove such heat from the heat generating device. For example, jet impingement may be used to cool a heat generating device by directing impingement jets of coolant fluid onto the heat generating device or a target surface that is thermally coupled to the heat generating device. Additionally, jet impingement may also be combined with two-phase cooling, where the heat generating device is cooled by the phase change of the coolant fluid from a liquid to a vapor. However, vapor bubbles are typically formed within the coolant fluid near the heat generating device. If not properly evacuated, vapor bubbles can lead to an increase in pressure drop and, if allowed to collect, lead to an increase in pressure within the cooling apparatus. The saturation temperature of the coolant fluid increases with increasing pressure, which adversely affects the performance of the two-phase heat transfer.
Accordingly, a need exists for alternative jet impingement, two-phase cooling apparatuses.